Guns are cool

September 21, 2013
By

(This article was first published on Wiekvoet, and kindly contributed to R-bloggers)

Reddit has a subreddit Guns are cool which in turn contains the MASS SHOOTINGS IN 2013 page. I pulled those data to see if there was anything of interest to plot or examine. I ended with modelling the frequency of shootings (once a day, Poisson distribution), and number of victims per shootings, a mixture of distributions, 2% of shootings are from a Poisson distribution with Lambda=15.

Data

Data are 264 records, spanning from January 1st to September 19th at the moment or writing. Rule for entry in this table: 'The only requirement is that four or more people are shot in a spree, likely without a cooling off period. This may include the gunman himself (because they often suicide by cop or use a gun to kill themselves to escape punishment), or police shootings of civilians around the gunman. The reasoning behind the latter being that if the shooter is arrested, he will often be charged with injuring people the police actually shot, as that is a foreseeable result of a shooting spree.' The data are not entered with the objective of machine processing, for instance records up to 6 show there are sometimes number of death, sometimes injured, sometimes both, in either order. The final entries on a row are location and state, the first are number and date, between it is messy, with random usage of commas and random number of entries between them.
Number 1: 1/1/13, Julian Sims, 4 injured, McKeesport, PA
Number 2: 1/1/13, Unknown, 1 dead 3 injured, Hawthorne, CA
Number 3: 1/1/13, Desmen Noble, Damian Bell, 1 dead 4 injured, Lorain, OH
Number 4: 1/5/13, Sonny Archuleta, 4 dead, Aurora, CO
Number 5: 1/7/13, Sandra Palmer, 2 dead 2 injured, Greensboro, NC
Number 6: 1/7/13, Herbert Bland Jr., 23, 3 dead 1 injured, Dinwiddie, VA
They have been processed using the following assumptions and steps:
  • The number before dead is the number of dead, same for injured. 
  • Final field is state. I know of one exception (Number 117: 5/26/13, Esteban J. Smith, 3 dead 5 injured, Eden, TX & Jacksonville, NC), but since I did not analyzed states I left it as processed.
  • US date format (MM/DD/YY)
  • anything between dead / injured and state is location.
  • anything between date and dead / injured can be ignored.
  • record 249 is incomplete: it misses '4 injured, Marion, NC'.
  • Washington DC, I know DC is not a state, but it sure made my processing easy to handle it as such.
  • Puerto Rico is removed from the analysis

Number of shootings in a day

The number of shootings very nicely follows a Poisson distribution with Lambda =1 (sd=0.06). The figure below shows the data (histogram) with fitted values (line).

Number of victims per shooting

For this analysis I will take the number of victims as number of dead plus number of injured. It is an interesting analysis, first of all data below 4 not registered. This lead me to choosing JAGS rather than fitdistr() to get an estimate. It is also appears a single Poisson distribution does not describe the data well. In the end a mixture of four distributions was used. The table below shows a small part (2%) of the shootings to come from a Poisson distribution with Lambda = 15. Combined with the number of shootings being 1 per day, this gives 3 to 4 really bad shootings per year. 
     Lambda     SD    Proportion    SD
0.870.360.550.16
3.1 1.2 0.340.15
7.1 2.7 0.090.08
15.4 2.4 0.020.01
The plot shows the data in a histogram, Poisson fit (blue) and four component mixture Poisson distribution (purple). The fit might be improved upon, but four distributions is pushing it with this limited range in data.

R-scripts

r1 <- readLines(textConnection('
Number 1: 1/1/13, Julian Sims, 4 injured, McKeesport, PA
Number 2: 1/1/13, Unknown, 1 dead 3 injured, Hawthorne, CA
Number 3: 1/1/13, Desmen Noble, Damian Bell, 1 dead 4 injured, Lorain, OH
Number 4: 1/5/13, Sonny Archuleta, 4 dead, Aurora, CO
Number 5: 1/7/13, Sandra Palmer, 2 dead 2 injured, Greensboro, NC
Number 6: 1/7/13, Herbert Bland Jr., 23, 3 dead 1 injured, Dinwiddie, VA
Number 7: 1/7/13, Cedric and James Poore (brothers), 4 dead, Tulsa, OK
Number 8: 1/11/13, Unknown, 4 dead, Sacramento, CA
Number 9: 1/19/13, Nehemiah Griego, 5 dead, Albuquerque, NM
Number 10: 1/21/13, Unknown, 4 injured, Brentwood, CA
Number 11: 1/25/13, Unknown, 1 dead 4 injured, St. Louis, MO
Number 12: 1/26/13, Unknown, 5 injured, Washington DC
Number 13: 1/27/13, Wilbert Thibodeaux, 1 dead 3 injured, Charenton, LA
Number 14: 1/30/13, Douglas Harmon, 3 dead 1 injured, Phoenix, AZ
Number 15: 2/1/13, Unknown, 1 dead 3 injured, Oakland, CA
Number 16: 2/2/13, Sundra Payne, 5 injured, Memphis, TN
Number 17: 2/3/13, Kong Meng Vue, Ryan Cha, Ken Cha, 1 dead 3 injured, Olivehurst, CA
Number 18: 2/3/13, Christopher Dorner, 5 dead 4 injured, Began in Riverside, CA
Number 19: 2/3/13, Jackie Spears & Kelcie Stewart, 2 dead 2 injured, Memphis, TN
Number 20: 2/6/13, Mayra Perez, 3 dead 1 injured, Denver, CO
Number 21: 2/7/13, Unknown, 4 injured, Chicago, IL
Number 22: 2/9/13, Malcolm Hall, Brandon Brown, Deron Bridgewater, 4 injured, New Orleans, LA
Number 23: 2/11/13, Nhan Lap Tran, 1 dead 4 injured, Oakdale, MN
Number 24: 2/11/13, Unknown, 1 dead 4 injured, Vallejo, CA
Number 25: 2/11/13, Thomas Matusiewicz, 3 dead 2 injured, Wilmington, DE
Number 26: 2/12/13, Two suspects, David Fresques in custody and Davis Fotu at large, 3 dead 1 injured, Suburban Salt Lake City(Midvale), UT
Number 27: 2/13/13, Joseph Matteson, 2 dead 2 injured, Red Springs, NC
Number 28: 2/16/13, Unknown, 1 dead 3 injured, Winston-Salem, NC
Number 29: 2/19/13, Ali Sayed, 4 dead 3 injured, Tustin, CA
Number 30: 2/21/13, Carlos Zuniga, 2 dead 2 injured, Miami, FL
Number 31: 2/21/13, Mark Hopkins, 1 dead 3 injured, Tulsa, OK
Number 32: 2/22/13, Unknown, 4 injured, Grand Rapids, MI
Number 33: 2/23/13, Unknown, 4 injured, Lancaster, CA
Number 34: 2/23/13, Unknown, 4 injured, Oakland, CA
Number 35: 2/24/13, Unknown, 8 injured, Macon, GA
Number 36: 3/2/13, Unknown, 1 dead 3 injured, Shreveport, LA
Number 37: 3/3/13, Unknown, 6 injured, Houston, TX
Number 38: 3/3/13, Unknown, 1 dead 3 injured, Moultrie, GA
Number 39: 3/4/13, Unknown, 4 injured, Saginaw, MI
Number 40: 3/4/13, Unknown, 1 dead 3 injured, Los Banos, CA
Number 41: 3/5/13, Unknown, 1 dead 3 injured, Indianapolis, IN
Number 42: 3/5/13, Unknown, 4 injured, Fuquay-Varina, NC
Number 43: 3/7/13, Joshua Hurst, 2 dead 2 injured, Jackson, MS
Number 44: 3/8/13, Unknown, 1 dead 3 injured, Buffalo, NY
Number 45: 3/10/13, Taleb Salameh, 3 dead 1 injured, North Liberty, IA
Number 46: 3/11/13, Taleb Hussein Yousef Salameh, 1 dead 3 injured, Iowa City, IA
Number 47: 3/11/13, Andrew Davon Allen and Craig Willson, 13 injured, Washington, DC
Number 48: 3/13/13, Unknown, 2 dead 2 injured, San Diego, CA
Number 49: 3/13/13, Kurt Myers, 5 dead 2 injured, Herkimer, NY
Number 50: 3/14/13, Unknown, 4 injured, Modesto, CA
Number 51: 3/15/13, Angelica Vazquez, 4 dead, Mesquite, TX
Number 52: 3/16/13, Unknown, 7 injured, Galt, CA
Number 53: 3/17/13, Unknown, 5 injured, Belle Glade, FL
Number 54: 3/17/13, Unknown, 2 dead 4 injured, Stockton, CA
Number 55: 3/20/13, Brandon Menefee, 3 dead 1 injured, Jefferson County, AL
Number 56: 3/21/13, Unknown, 7 injured, Chicago, IL
Number 57: 3/21/13, Unknown, 1 dead 4 injured, Kansas City, MO
Number 58: 3/22/13, Unknown, 1 dead 3 injured, New York, NY
Number 59: 3/26/13, Unknown, 4 injured, St. Petersberg, FL
Number 60: 3/31/13, Unknown, 2 dead 3 injured, Merced County, CA
Number 61: 3/31/13, Unknown, 3 dead 1 injured, Auburn, WA
Number 62: 4/2/13, Unknown, 4 dead 1 injured, San Juan, Puerto Rico
Number 63: 4/6/13, Unknown, 1 dead 4 injured, Greenwood, SC
Number 64: 4/6/13, Unknown spree shooter, 4 injured, Philadelphia, PA
Number 65: 4/7/13, Unknown, 1 dead 3 injured, Long Beach, CA
Number 66: 4/7/13, 1 in custody, name withheld, 1 dead 3 injured, Manhatten, Kansas
Number 67: 4/9/13, Unknown, 1 dead 3 injured, Philadelphia, PA
Number 68: 4/10/13, Unknown, 4 injured, Vallejo, CA
Number 69: 4/13/13, Trenton Ore, Joven Covington, 5 injured, Norfolk, VA
Number 70: 4/13/13, Unknown, 4 injured, Merced, CA
Number 71: 4/14/13, Unknown, 1 dead 4 injured, Lexington, KY
Number 72: 4/14/13, Unknown, 2 dead 4 injured, Phoenix, AZ
Number 73: 4/18/13, Unknown, 4 dead, Akron, OH
Number 74: 4/20/13, Unknown, 2 dead 2 injured, Modesto, CA
Number 75: 4/20/13, Christine Squire, 2 dead 2 injured, Richmond, VA
Number 76: 4/21/13, Unknown, 5 dead 2 injured, Federal Way, WA
Number 77: 4/22/13, Davante Robertson, Charlie A. Gumms, Frankie Hookman, Jr and Lashawn Davis, 5 injured, Havey, Louisiana
Number 78: 4/22/13, Unknown, 4 injured, Englewood, Illinois
Number 79: 4/24/13, Rick Odell Smith, 6 dead 1 injured, Manchester, IL
Number 80: 4/25/13, Sean M. Woodings, 4 injured, Oberlin, Ohio
Number 81: 4/27/13, Unknown, 1 dead 4 injured, Williston, FL
Number 82: 4/28/13, Unknown, 5 injured, Charlotte, NC
Number 83: 4/28/13, Neville Lynch, Mark Rose, 4 injured, Lauderdale Lakes, FL
Number 84: 4/28/13, Unknown, 2 dead 2 injured, Jackson, Tennessee
Number 85: 4/28/13, Unknown drive-by, 1 dead 3 injured, Chester, PA
Number 86: 5/2/13, Unknown, 5 injured, Newark, NJ
Number 87: 5/4/13, Unknown drive-by, 4 dead 6 injured, Aguas Buenas, PR
Number 88: 5/4/13, Krystal Olymica David, 4 injured, Smithfield, NC
Number 89: 5/5/13, Unknown, 1 dead 3 injured, Oakland, CA
Number 90: 5/5/13, Unknown drive-by, 6 injured, E. Palo Alto, CA
Number 91: 5/6/13, Two boys, 10, 11, 4 injured, Ocean Township, NJ
Number 92: 5/6/13, Unknown, 4 injured, Johnstown, PA
Number 93: 5/8/13, Ralph Robert Warren III, 4 dead, Hendersonville, NC
Number 94: 5/10/13, Unknown, 3 dead 1 injured, Harbor Gateway (Los Angeles), CA
Number 95: 5/11/13, Unknown, 4 injured, East Germantown, PA
Number 96: 5/11/13, Samuel E. Sallee, 4 dead, Waynesville, IN
Number 97: 5/12/13, Unknown, 5 injured, Newark, NJ
Number 98: 5/12/13, Unknown, 4 injured, Hollister, CA
Number 99: 5/12/13, Unknown, 19 injured, New Orleans, LA
Number 100: 5/12/13, Unknown, 4 injured, Apache Junction, AZ
Number 101: 5/12/13, Unknown, 4 injured, Jersey City, NJ
Number 102: 5/13/13, Unknown, 5 injured, Winton Hills, OH
Number 103: 5/15/13, Arrest made 5/21, 1 dead 4 injured, Detroit, MI
Number 104: 5/15/13, Jeremiah Bean, 5 dead, Fernley, NV
Number 105: 5/16/13, Unknown, 4 injured, Philladelphia, PA
Number 106: 5/18/13, Unknown, 3 dead 3 injured, Las Piedras, PR
Number 107: 5/19/13, Unknown, 4 injured, Detroit, MI
Number 108: 5/19/13, Codarrell Lee Yates, 4 injured, Lunenburg, VA
Number 109: 5/19/13, Unknown, 2 dead 2 injured, South Memphis, TN
Number 110: 5/20/13, Unknown, 4 injured, Chicago, IL
Number 111: 5/21/13, Unknown, 4 injured, Madison County, AL
Number 112: 5/23/13, Jason Brian Holt, 2 dead 2 injured, Knoxville, TN
Number 113: 5/23/13, Evellis T. McGee and Karon D. Thomas, 1 dead 3 injured, Saginaw, MI
Number 114: 5/24/13, Julio Jesus Romero, 2 dead 2 injured, Bakersfield, CA
Number 115: 5/25/13, Antonio King Green, 1 dead 3 injured, Flint, MI
Number 116: 5/25/13, Ryan Taybron, 15, and Eric Nixon, 17, 1 dead 4 injured, Hampton, VA
Number 117: 5/26/13, Esteban J. Smith, 3 dead 5 injured, Eden, TX & Jacksonville, NC
Number 118: 5/28/13, Unknown, 1 dead 3 injured, Memphis, TN
Number 119: 5/28/13, Unknown, 5 dead, Sells, AZ
Number 120: 5/29/13, Unknown, 4 injured, Chicago (Bronzeville), IL
Number 121: 5/31/13, Unknown, 4 injured, Atlanta, GA
Number 122: 6/1/13, Unknown, 2 dead 2 injured, Vallejo, CA
Number 123: 6/1/13, Unknown, 4 injured, Milwaukee, WI
Number 124: 6/2/13, Unknown, 4 injured, Indianapolis, IN
Number 125: 6/2/13, Unknown, 4 injured, Virginia Beach, VA
Number 126: 6/2/13, Unknown, 5 injured, Roanoke, VA
Number 127: 6/2/13, Xavier Edmondson and Lewis Antonio, 7 injured, LaGrange, GA
Number 128: 6/3/13, Manuel Mata III, 2 dead 2 injured, Las Vegas, NV
Number 129: 6/4/13, Johnny Simpson, 2 dead 2 injured, Shoreview, MN
Number 130: 6/5/13, St. Charles resident, 10 injured, Elburn, IL
Number 131: 6/7/13, John Zawahri, 5 dead 5 injured, Santa Monica, CA
Number 132: 6/9/13, Unknown, 4 injured, York City, PA
Number 133: 6/10/13, Unknown, 1 dead 5 injured, Chicago, IL
Number 134: 6/10/13, Davonta Coleman, 6 injured, St. Louis, MO
Number 135: 6/11/13, David Andrus, 4 dead, Darien, IL
Number 136: 6/12/13, Ahmed Dirir, 4 dead, St. Louis, MO
Number 137: 6/14/13, Unknown, 4 injured, High Point, NC
Number 138: 6/15/13, Earnest Woodley, 4 injured, Nashville, TN
Number 139: 6/15/13, Unknown, 1 dead 3 injured, Houston, TX
Number 140: 6/16/13, Unknown, 1 dead 3 injured, Chicago, IL
Number 141: 6/18/13, Unknown, 1 dead 3 injured, Berkeley, MO
Number 142: 6/19/13, Gary W. Stewart Jr., 3 dead 1 injured, Louisville, KY
Number 143: 6/21/13, Darren Lamont Roberts and Kyle Edward Thornton, 6 injured, Norfolk, VA
Number 144: 6/21/13, Unknown, 1 dead 3 injured, (Kelvyn Park) Chicago, IL
Number 145: 6/22/13, Unknown, 1 dead 4 injured, Baltimore, MD
Number 146: 6/22/13, Kamal “Rico” Edge, 1 dead 4 injured, Paterson, NJ
Number 147: 6/22/13, Unknown, 4 injured, Providence, RI
Number 148: 6/22/13, Lakim Anthony Faust, 5 injured, Greenville, NC
Number 149: 6/23/13, Unknown, 4 injured, Gentilly, LA
Number 150: 6/23/13, Unknown, 1 dead 3 injured, Chattanooga, TN
Number 151: 6/23/13, Unknown, 1 dead 4 injured, Virginia Beach, VA
Number 152: 6/23/13, Unknown, 1 dead 8 injured, Kansas City, MO
Number 153: 6/23/13, Elijah Rodgers, 1 dead 3 injured, Sacramento, CA
Number 154: 6/24/13, Unknown, 1 dead 3 injured, Kansas City, MO
Number 155: 6/25/13, Unknown, 1 dead 4 injured, Chicago, IL
Number 156: 6/27/13, Manuel Talamantez, Christina Martinez, 2 dead 2 injured, Three Rivers, CA
Number 157: 6/27/13, Tierra Fallin, 1 dead 3 injured, Baltimore, MD
Number 158: 6/28/13, Unknown, 6 injured, Chicago, IL
Number 159: 6/29/13, Ronald Reid, Barry Stinson, 3 dead 1 injured, North Charleston, SC
Number 160: 6/29/13, Unknown, 4 injured, Aurora, CO
Number 161: 6/30/13, Unknown, 9 injured, Brooklyn, NY
Number 162: 7/1/13, Amos Wells, 4 dead, Fort Worth, TX
Number 163: 7/2/13, Unknown, 1 dead 3 injured, Montgomery, AL
Number 164: 7/3/13, Unknown, 1 dead 3 injured, Calais, Maine
Number 165: 7/4/13, Robert Marion Naylor, 1 dead 6 injured, Pontiac, MI
Number 166: 7/4/13, Unknown, 4 injured, Woodlawn, IL
Number 167: 7/5/13, Unknown, 1 dead 3 injured, Macon, GA
Number 168: 7/6/13, Brandon Reese, 1 dead 3 injured, Brooklyn, NY
Number 169: 7/6/13, Unknown, 1 dead 7 injured, Chicago, IL
Number 170: 7/6/13, Chauncy Laray Mitchell, 4 injured, Florence, AL
Number 171: 7/6/13, Unknown, 1 dead 3 injured, Los Angeles, CA
Number 172: 7/7/13, Unknown, 1 dead 4 injured, Stockton, CA
Number 173: 7/7/13, Unknown, 1 dead 3 injured, Pompano Beach, FL
Number 174: 7/7/13, Unknown, 4 injured, Meridian, Miss.
Number 175: 7/7/13, Unknown, 1 dead 5 injured, Chicago, IL
Number 176: 7/9/13, Lamont Jones, 4 injured, Balimore, MD
Number 177: 7/9/13, Unknown, 2 dead 2 injured, Rockford, IL
Number 178: 7/10/13, Konrad Schafer, 15, and David Damus, 20, 2 dead 12 injured, Kissimmee, FL
Number 179: 7/11/13, Unknown, 1 dead 3 injured, Charlotte, NC
Number 180: 7/12/13, Unknown, 2 dead 2 injured, Greensburg, KY
Number 181: 7/12/13, Unknown, 1 dead 3 injured, San Francicsco, CA
Number 182: 7/12/13, Unknown, 1 dead 4 injured, Hamilton Township, NJ
Number 183: 7/13/13, Unknown, 4 injured, Washington DC
Number 184: 7/13/13, Unknown, 1 dead 3 injured, Oklahoma City, OK
Number 185: 7/13/13, Unknown, 5 dead 1 injured, New Orleans, LA
Number 186: 7/14/13, Unknown, 1 dead 4 injured, Wichita, KS
Number 187: 7/14/13, Suspect in custody., 5 injured, Kentwood, MI
Number 188: 7/14/13, Phillip Brierly Jr., 2 dead 2 injured, Lexington, SC
Number 189: 7/17/13, Unknown, 3 dead 1 injured, Oakland, CA
Number 190: 7/19/13, Unknown, 4 injured, Madera, CA
Number 191: 7/19/13, Unknown, 4 injured, Hartford, CT
Number 192: 7/20/13, Devin Spann, 5 injured, Campbell, OH
Number 193: 7/21/13, Unknown, 4 injured, Brooklyn (Crown Heights), NY
Number 194: 7/21/13, Unknown, 5 injured, Brooklyn (Bushwick), NY
Number 195: 7/21/13, Unknown, 2 dead 2 injured, Fort Pierce, FL
Number 196: 7/21/13, Terrence Lynom, Angelo Clark, 1 dead 3 injured, Chicago, IL
Number 197: 7/24/13, Unknown, 4 injured, Topeka, KS
Number 198: 7/25/13, Unknown, 4 injured, Inkster, MI
Number 199: 7/26/13, Sidney A. Muller, 4 dead, Clarksburg, WV
Number 200: 7/26/13, Unknown, 7 dead, Hialea, FL
Number 201: 7/27/13, Unknown, 1 dead 3 injured, Farmington, NM
Number 202: 7/28/13, Unknown, 4 injured, Granger, WA
Number 203: 7/28/13, Unknown, 1 dead 3 injured, Irvington, NJ
Number 204: 7/28/13, Unknown, 5 injured, Dallas, TX
Number 205: 7/30/13, Parrish Chee, 4 injured, Lea County (Hobbs), NM
Number 206: 8/2/13, Tristan Crayton, 4 injured, Broad Ripple, IN
Number 207: 8/2/13, Unknown, 4 dead, Whitesburg, KY
Number 208: 8/2/13, Unknown, 2 dead 3 injured, Newark, NJ
Number 209: 8/3/13, Unknown, 5 injured, Detriot, MI
Number 210: 8/4/13, Giovanni Pacheco, 3 dead 4 injured, Salinas, CA
Number 211: 8/4/13, Unknown, 1 dead 3 injured, Kansas City, Mo
Number 212: 8/5/13, Rockne Newell, 3 dead 4 injured, Ross Township, PA
Number 213: 8/5/13, Suspect known., 4 injured, Montclair, NJ
Number 214: 8/7/13, Erbie Bowser, 4 dead 4 injured, Dallas, TX
Number 215: 8/11/13, Nikko Jenkins, 4 dead, Omaha, NE
Number 216: 8/11/13, Unknown, 1 dead 3 injured, Flatbush, NY
Number 217: 8/11/13, Unknown, 1 dead 4 injured, Portsmouth, VA
Number 218: 8/11/13, Unknown, 4 injured, Wilmington, Del.
Number 219: 8/11/13, Unknown, 2 dead 2 injured, St. Louis, MO
Number 220: 8/12/13, Unknown, 4 injured, Cincinnati, OH
Number 221: 8/16/13, Unknown, 4 injured, Kingsessing, PA
Number 222: 8/17/13, Demetrius Ward, 4 injured, Oakland, CA
Number 223: 8/18/13, Unknown, 1 dead 3 injured, Chicago, IL
Number 224: 8/18/13, Darryl Sain, 4 injured, St. Louis, MO
Number 225: 8/18/13, Dontrel Shyhee Blakeney, 17, 1 dead 4 injured, Chesterfield County, SC
Number 226: 8/18/13, Unknown, 1 dead 3 injured, Rochester, NY
Number 227: 8/18/13, Unknown, 4 injured, Port Norris, NJ
Number 228: 8/18/13, Unknown, 4 injured, Toledo, OH
Number 229: 8/19/13, Suspects in custody., 1 dead 4 injured, Chicago, IL
Number 230: 8/20/13, Unknown, 4 injured, Vanceboro, NC
Number 231: 8/20/13, Daniel Livingston Green, 4 dead, Oklahoma City, OK
Number 232: 8/20/13, Melville Mason, 2 dead 2 injured, Baltimore, MD
Number 233: 8/22/13, Jim Edwards, 2 dead 2 injured, Shaler, PA
Number 234: 8/23/13, Unknown, 1 dead 6 injured, Baltimore, MD
Number 235: 8/24/13, Unknown, 4 injured, Indianapolis, IN
Number 236: 8/25/13, Hubert Allen, Jr., 3 dead 2 injured, Lake Butler, FL
Number 237: 8/25/13, Unknown, 2 dead 2 injured, Minneapolis, MN
Number 238: 8/25/13, Unknown, 1 dead 4 injured, Dillon County, SC
Number 239: 8/25/13, Unknown, 4 injured, Oakland, CA
Number 240: 8/28/13, Devonere Simmonds, 3 dead 2 injured, Columbus, OH
Number 241: 9/5/13, Unknown, 4 injured, Charlotte, NC
Number 242: 9/7/13, Unknown, 2 dead 4 injured, Gary, IN
Number 243: 9/7/13, Darnell Hollings, 1 dead 3 injured, St. Louis, MO
Number 244: 9/10/13, Roderick Rodgers, 1 dead 4 injured, Bridgeport, CT
Number 245: 9/11/13, Unknown, 1 dead 3 injured, Washington DC
Number 246: 9/11/13, Unknown, 4 injured, New York, NY
Number 247: 9/12/13, Jacob Bennett, Brittany Moser, 4 dead, Renegade Mountain, TN
Number 248: 9/13/13, Unknown, 4 injured, Centreville, IL
Number 249: 9/14/13, Earl Spencer Boyce
Number 250: 9/15/13, Unknown, 6 injured, Yakima, WA
Number 251: 9/15/13, Unknown, 5 injured, Colorado Springs, CO
Number 252: 9/15/13, Unknown, 7 injured, Fresno, CA
Number 253: 9/15/13, Unknown, 2 dead 2 injured, Bakersfield, CA
Number 254: 9/15/13, Robert E. Bell, 3 dead 1 injured, Snellville, GA
Number 255: 9/15/13, Unknown, 4 injured, Wilmington, DE
Number 256: 9/16/13, Aaron Alexis, 13 dead 8 injured, Washington DC
Number 257: 9/17/13, Unknown, 1 dead 4 injured, Stockton, CA
Number 258: 9/17/13, Unknown, 4 injured, Lansing, MI
Number 259: 9/17/13, Unknown, 4 injured, Las Vegas, NV
Number 260: 9/17/13, Unknown, 4 dead, West Broward, FL
Number 261: 9/18/13, Unknown, 1 dead 4 injured, Whitehaven, TN
Number 262: 9/18/13, Unknown, 5 injured, Kissimmee, FL
Number 263: 9/18/13, Unknown, 1 dead 4 injured, Bakersfield, CA
Number 264: 9/19/13, Unknown, 13 injured, Chicago, IL
'),)
#empty first & last line
r1[r1=='Number 249: 9/14/13, Earl Spencer Boyce'] <-
    'Number 249: 9/14/13, Earl Spencer Boyce, 4 injured, Marion, NC'
r2 <- gsub('Number ','',r1[r1!=''])
mydf <- data.frame(Number=as.numeric(gsub(':.*$','',r2)))
r3 <- gsub('^.*: ','',r2)
mydf$Date <- as.Date(gsub('/13, .*$','/13',r3),format='%m/%d/%y')
r4 <- gsub('^.*/13, ', '',r3)
r4 <- gsub('dead ','dead, ',r4)
r4 <- gsub('injured ','injured, ',r4)
r4 <- gsub('Washington DC','Washington, DC',r4)
r5 <- strsplit(r4,',')
r4[sapply(r5,length)>5]
grep('TX & ',r1,value=TRUE)
#mydf$nfield <- sapply(r5,length)

mydf$state <- unlist(sapply(r5,function(x) 
          gsub(' ','',x[length(x)])))
mydf$dead <- sapply(r5,function(x) 
      as.numeric(gsub('dead','',grep('dead',x,value=TRUE)[1])))
mydf$injured <- sapply(r5,function(x) 
      as.numeric(gsub('injured','',grep('injured',x,value=TRUE)[1])))

mydf$location <- sapply(r5,function(x) {
      end <- length(x)-1
      begin <- max(grep('injured|dead',x))+1
      if (begin==-Inf) print(x) 
      substring(paste(x[begin:end]),2)[1]
    })
mydf$dead[is.na(mydf$dead)] <- 0
mydf$injured[is.na(mydf$injured)] <- 0

mydf$state[mydf$state=='Illinois'] <- 'IL'
mydf$state[mydf$state=='Kansas'] <- 'KS'
mydf$state[mydf$state=='Louisiana'] <- 'LA'
mydf$state[mydf$state=='Tennessee'] <- 'TN'
mydf$state[mydf$state=='Maine'] <- 'ME'
mydf$state[mydf$state=='Ohio'] <- 'OH'
mydf$state[mydf$state=='Miss.'] <- 'MS'
mydf$state[mydf$state=='Del.'] <- 'DE'

mydf <- mydf[mydf$state!='PuertoRico',]

mydf$Victims <- mydf$dead+mydf$injured
plot(dead ~ injured,data=mydf)

# How often in a day?
library(ggplot2)

mydf$fDate <- factor(
    levels=as.character(seq(min(mydf$Date),max(mydf$Date),by=1)),
    as.character(mydf$Date))
fperday <- as.data.frame(table(table(mydf$fDate)))
png('freqinday.png')
g1 <- ggplot(fperday,aes(x=Var1,y=Freq))
g1 + geom_bar(stat='identity') +
    labs(x='Number of Shootings',
        y='Number of days') +
    geom_line(data=
            data.frame(Var1=1:7,
                Freq=dpois(0:6,
                    lambda=MASS::fitdistr(table(mydf$fDate),
                        densfun='Poisson')$estimate)*nrow(mydf)
            ),
        colour='blue')
dev.off()
str(MASS::fitdistr(table(mydf$fDate),
        densfun='Poisson'))
# # of victims per shooting
mydf$fVictims <- factor(levels=4:max(mydf$Victims),mydf$Victims)
freqdf <- as.data.frame(table(mydf$fVictims))
freqdf$Nvic <- as.numeric(as.character(freqdf$Var1))
library(R2jags)
datain <- list(Victims=mydf$Victims,
    N=nrow(mydf))

Fmodel <- function() {
  for (i in 1:N) {
    Victims[i] ~ dpois(lambda) %_% T(4,)
  }
  lambda ~ dunif( 0, 20)  
}

params <- c('lambda')
inits <- function() {
  list(lambda = runif(1,1,3))
}

jagsfit <- jags(datain, model=Fmodel, inits=inits, parameters=params,
    progress.bar="gui")

#jagsfit
freqdf$exp1 <- dpois(freqdf$Nvic,lambda=2.890)*sum(mydf$Victims)
#2.890
freqdf

#g1 <- ggplot(freqdf,aes(x=Nvic,y=Freq))
#g1 + geom_bar(stat='identity') +
#    labs(x='Number of victims',
#        y='Frequency') +
#    geom_line(data=
#            data.frame(Nvic=4:15,
#                Freq=dpois(4:15,
#                    lambda=2.890)*sum(mydf$Victims)
#            ),
#        colour='blue')

#http://doingbayesiandataanalysis.blogspot.nl/2012/06/mixture-of-normal-distributions.html

Fmodel3 <- function() {
  for (i in 1:N) {
    j[i] ~ dcat(pp) 
    Victims[i] ~ dpois(lambdas[j[i]]  )   %_% T(4,)
  }
  lambda[1] ~ dunif( 0, 20)
  lambda[2] ~ dunif(0,20 )
  lambda[3] ~ dunif(0,20 )
  lambda[4] ~ dunif(0,20 )
  lambdas <- sort(lambda)
  p[1] <- 3
  p[2] <- 3
  p[3] <- 1
  p[4] <- 1
  pp[1:4] ~ ddirch( p )
}

params3 <- c('lambdas','pp')
inits3 <- function() {
  list(lambda = c(runif(1,1,3),runif(1,1,3),runif(1,6,8),runif(1,8,20)))
}

jagsfit3 <- jags(datain, model=Fmodel3, inits=inits3, parameters=params3,
    progress.bar="gui",n.iter=10000)
#jagsfit3
#mcmc3 <- as.mcmc(jagsfit3)
#par(ask=TRUE)
#plot(mcmc3)

freqdf$exp4a <- sum(mydf$Victims)*dpois(freqdf$Nvic,lambda=0.87)*(.54)
freqdf$exp4b <- sum(mydf$Victims)*dpois(freqdf$Nvic,lambda=3.097)*(.337)
freqdf$exp4c <- sum(mydf$Victims)*dpois(freqdf$Nvic,lambda=7.101)*(.093)
freqdf$exp4d <- sum(mydf$Victims)*dpois(freqdf$Nvic,lambda=15.396)*(.023)


freqdf$exp4 <- freqdf$exp4a+freqdf$exp4b+freqdf$exp4c+freqdf$exp4d
png('numvictim.png')
g1 <- ggplot(freqdf,aes(x=Nvic,y=Freq))
g1 + geom_bar(stat='identity') +
    labs(x='Number of victims',
        y='Frequency') +
    geom_line(data=data.frame(Nvic=freqdf$Nvic,Freq=freqdf$exp1), colour='blue') +
    geom_line(data=data.frame(Nvic=freqdf$Nvic,Freq=freqdf$exp4),colour='purple') 
dev.off()

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